Japanese Prime Minister Shigeru Ishiba's fate remained unclear on Wednesday after he denied reports that he would resign his post at the end of next month.

"Nothing that has been reported is true," Ishiba was quoted as saying by The Japan Times Wednesday afternoon.

The Mainichi had reported earlier that Ishiba would announce his resignation by the end of August, following the Liberal Democratic Party's defeat in Japan's upper house election.

The report came hours after Japan and the United States reached a trade agreement to reduce the "reciprocal" tariff rate from 25 to 15 percent.

"I'll do my best to make sure that people's livelihood is protected," Ishiba said in reference to the tariff agreement, after a meeting with three former prime ministers - Taro Aso, Yoshihide Suga and Fumio Kishida.

Ishiba said the LDP heavyweights shared a common awareness that the party is at a critical juncture and that it must stay unified, The Japan Times reported.

The prime mister said his current standing was not discussed, according to The Japan Times.